B&H Electrical Engineering最新文献

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Data Acquisition and Simulation Software as Tools for Medium Voltage Switchgear Assessment and Optimization 作为中压开关柜评估与优化工具的数据采集与仿真软件
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0011
Maroua O Touhami, E. Sokic, Amer Smajkic, Andres Laso, N. Uzelac
{"title":"Data Acquisition and Simulation Software as Tools for Medium Voltage Switchgear Assessment and Optimization","authors":"Maroua O Touhami, E. Sokic, Amer Smajkic, Andres Laso, N. Uzelac","doi":"10.2478/bhee-2021-0011","DOIUrl":"https://doi.org/10.2478/bhee-2021-0011","url":null,"abstract":"Abstract This paper describes the advantages of using data acquisition systems and software modelling tools to support the assessment and therefore redesign of the existing medium voltage switchgear. A 38kV/630A load break linear puffer (LP) will be used as an example for this study. In house testing was conducted to capture important design parameters of the switch such as displacement, velocity of mechanical parts and gas pressure using various sensors and three different measurement setups. The first setup, which is primarily intended for no-load measurements, consists of a DAQ system equipped with different types of sensors - two rotational encoders, three laser-based distance sensors, six pressure sensors, contact separation measurement, and a high-speed camera integrated and synchronized with the measurement system. The second and third setups, which are suitable both for no-load and on-load measurements, are based on state-of-the-art DAQ systems, which use three piezo-electric based pressure sensors, two fibre-optic based pressure sensors, three laser-based distance sensors and a high speed camera synchronized with the measurement system. The data acquired by the measurement systems is used in combination with an in-house developed simulation software HV CB Simulation, which enables simulating and predicting various variables of switching devices. Moreover, high speed camera videos analysed with both commercial and in-house developed image processing software, visualize and reveal many otherwise inaccessible occurrences. In addition to a comprehensive analysis of the proposed data acquisition and simulation setups, three design improvements in the linear puffer design - increase of the opening speed, removal of the flexible conductors and the length increase of the puffer cylinder - are presented and discussed in this paper.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":" 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113948471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Innovative T&D Switching Equipment and Development of its Testing Technology 新型T&D开关设备及其测试技术的发展
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0001
R. Smeets, Arman Derviškadić, Adriaan Hofstee, R. M. Nijman, N. Belda, Benjamin Baum
{"title":"Innovative T&D Switching Equipment and Development of its Testing Technology","authors":"R. Smeets, Arman Derviškadić, Adriaan Hofstee, R. M. Nijman, N. Belda, Benjamin Baum","doi":"10.2478/bhee-2021-0001","DOIUrl":"https://doi.org/10.2478/bhee-2021-0001","url":null,"abstract":"Abstract A short overview of the developments in the overall transmission and distribution industry in South East Europe is presented in this contribution. Furthermore, as the present journal focuses on breaking and switching in HV and MV switchgears, several technology innovations in T&D switchgear have been identified, at global level. In almost all cases, the ongoing energy transition is the main driver of these innovations. In this contribution, based on test-experience and overview of the industry, innovations are grouped by drivers, with each of them having its impact on testing technology. These drivers are the following: 1. Increase of ratings: the ongoing trend of co-existence of micro-, local- and super-grids. The consequences for testing of switchgear for UHV and very large current are highlighted: 2. Offshore transmission: compactness and reliability are requirements stretched to the limit for this application. Very long cables for AC and HVDC power transmission, even in a multi-terminal topology will have impact on switchgear. 3. Health safety and environment: here, the major switchgear related discussion is on SF6 replacement and reduction of electrical losses. Various issues related to SF6 replacement will be highlighted. In addition, a recent project intended to quantify the hazard of aluminium bus bars in power stations affected by long duration fault arcs is described. 4. HVDC and power electronics: circuit breakers are going to be installed in multi-terminal HVDC grids. Testing of HVDC breakers, regarding the complete interruption current process is described. 5. Digitalization: switchgear is going to be communicating with the IEC 61850 communication protocol. This will impact testing for which laboratories need to prepare. The introduction of smaller micro-electronics (sensors, IED) closer to primary HV components and its high-frequency transients need careful consideration regarding operation, endurance, and lifetime. 6. Resilience and fault mitigation: Resilience against severe weather conditions, vandalism and cyber-attacks calls for resistant equipment and robust mobile equ ipment/substations that can 6be deployed very rapidly still having an extreme degree of readiness and availability. 7. Quality assurance of products in the face of a pandemic and a lockdown requires adequate methods of a remote digital access to test, and factory sites for type testing and inspection.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128659203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Global Warming Potential Considerations for Gaseous Sf6 Alternatives Along the Switchgear Lifetime 气体Sf6替代品在开关设备使用寿命期间的全球变暖潜势考虑
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0004
Xiangyang Ye, J. Mantilla
{"title":"Global Warming Potential Considerations for Gaseous Sf6 Alternatives Along the Switchgear Lifetime","authors":"Xiangyang Ye, J. Mantilla","doi":"10.2478/bhee-2021-0004","DOIUrl":"https://doi.org/10.2478/bhee-2021-0004","url":null,"abstract":"Abstract Next-generation environmentally friendly switchgear will not use SF6. Currently, all of the main manufacturers in the world are developing products using alternatives based on CO2 as a background gas. The use of FluoroNitriles, 3M™ Novec™ 4710, C4F7N (C4FN) is addressed by different producers under different trademark names. In most cases, Oxygen is added for health and/or functional reasons. In terms of potential climate impact, considering only the GWP of the single gas mixture components is insufficient. In order to better evaluate and understand the advantages the different alternatives offer in comparison to SF6, the GWP calculations of the gas mixtures over a defined timeframe are much more complete. Additionally, not only the GWP of the gas mixtures in new condition is to be considered, but also their evolution through the switchgear lifetime. Arcing, created in all switching and interrupting test duties of HVCB will cause reversible and irreversible chemical reactions that produce new compounds with different dielectric, arc quenching, and environmental properties as the original molecule. Based on thermodynamic calculations, CFD simulations, and gas analysis of samples of alternatives that have been subjected to arcing, this work studies the effect the byproducts of the different mixtures have in terms of climate impact, dielectrics, and arc quenching. This paper offers different scenarios of electrical and gas degradation, from very uncommon events e.g., T100s to very common ones e.g., switching of nominal and/or capacitive currents. The influence of the always evolving gas mixtures along the lifetime of the equipment is evaluated and compared in terms of performance and the climate impact.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131281266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
High Voltage Circuit Breaker Vibration Signature Indices Evaluation for Condition Assessment 高压断路器状态评估振动特征指标评价
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0010
Kerim Obarcanin, Dzenita Skulj, B. Lacevic
{"title":"High Voltage Circuit Breaker Vibration Signature Indices Evaluation for Condition Assessment","authors":"Kerim Obarcanin, Dzenita Skulj, B. Lacevic","doi":"10.2478/bhee-2021-0010","DOIUrl":"https://doi.org/10.2478/bhee-2021-0010","url":null,"abstract":"Abstract The importance of the high voltage circuit breaker for the power system’s safe and reliable operation is paramount. This research aims to analyse and provide the most significant high voltage circuit breaker health state indices based on the non-invasive vibration fingerprint measurement method. Results obtained and presented in this paper are validated on the data set acquired from the vacuum circuit breaker.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126182433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Study on Arc Evolution Behaviour of Breaking Short Circuit Current for a Fast Vacuum Circuit Breaker 快速真空断路器开断短路电流电弧演化特性研究
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0003
Jianhua Wang, Chen Guan, Bojian Zhang, X. Yao, Zhiyuan Liu, Yingsan Geng
{"title":"Study on Arc Evolution Behaviour of Breaking Short Circuit Current for a Fast Vacuum Circuit Breaker","authors":"Jianhua Wang, Chen Guan, Bojian Zhang, X. Yao, Zhiyuan Liu, Yingsan Geng","doi":"10.2478/bhee-2021-0003","DOIUrl":"https://doi.org/10.2478/bhee-2021-0003","url":null,"abstract":"Abstract A fast vacuum circuit breaker (FVCB), driven by an electromagnetic repulsion mechanism, has an extremely short opening time, and in coordination with the controlled switching technology contributes to breaking a short circuit current with the minimum arcing time. The objective of the paper is to determine the arc evolution behaviour of fast vacuum circuit breakers with a minimum arcing time. A 40.5 kV vacuum interrupter (VI) was used, which was equipped with a pair of CuCr50 (Cr 50 wt%) axial magnetic field (AMF) contacts. The diameters of the contact were Φ50mm, Φ58 mm and Φ65 mm respectively. The arc evolution behaviour in the drawn arc experiment was photographed by a high-speed camera through a glass envelope of the VI. The experiment results showed that an initial intense arc tended to evolve into a diffuse arc when the arcing time is larger than a critical arc diffusion time under a certain opening velocity. The critical arc diffusion time for the vacuum arc is defined as arc evolving from the instant of contact separation to an appearance of separated cathode spots. For a Φ50 mm cup-type AMF contact, the critical arc diffusion time decreases from 0.7 ms to 0.46 ms, with the increase of the opening velocity from 2.52 m/s to 4.65 m/s. What’s more, for a Φ58 mm cup-type AMF contact, the critical arc diffusion time decreases from 1.0 ms to 0.58 ms with the increase of the opening velocity from 2.52 m/s to 4.65 m/s. For a Φ65 mm cup-type AMF contact, the critical arc diffusion time decreases from 1.30 ms to 0.64 ms with the increase of the opening velocity from 2.52 m/s to 4.65 m/s. The critical arc diffusion time increases with the increase of the diameter of the contact under the same opening velocity.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"379 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122180448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study of Shock Wave Development in Cold Flow of Gas Circuit Breaker for Improving Capacitive Current Switching 改进容性电流开关的气体断路器冷流激波发展研究
B&H Electrical Engineering Pub Date : 2021-10-01 DOI: 10.2478/bhee-2021-0008
Wei Gu, Ruyuan Tian, Zide Guo, D. Feng
{"title":"Study of Shock Wave Development in Cold Flow of Gas Circuit Breaker for Improving Capacitive Current Switching","authors":"Wei Gu, Ruyuan Tian, Zide Guo, D. Feng","doi":"10.2478/bhee-2021-0008","DOIUrl":"https://doi.org/10.2478/bhee-2021-0008","url":null,"abstract":"Abstract Capacitive current switching performance of SF6 circuit breaker is determined by combined action of gas flow and electric field in interruption chamber. Computational fluid dynamics method is used to study the development of shock waves inside a SF6 circuit breaker under the condition of capacitive current switching. It was found that a shock wave exists and travels with the pin contact during the contact opening. Existence of shock waves reduces the local gas density around contact head, while the contact head is also stressed by high electric field at the same time. If the region of low gas density coincides with the region with high electric strength, local dielectric performance will be significantly reduced. Using E/ρ as the dielectric performance index, when the local value of E/ρ exceeds the gas breakdown criterion, it will result in restrike to the capacitive current switching. The causes of high E/ρ are studied by analyzing the shock waves during the sequential periods of contact travel. Since the gap between the pin contact and nozzle throat strongly affects the strength of shock wave, the behavior of gap is studied with the calculation of E/ρ to find its influence on capacitive current switching.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121820672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Case Study: Security of System for Remote Management of Windows 案例研究:Windows远程管理系统的安全性
B&H Electrical Engineering Pub Date : 2020-12-01 DOI: 10.2478/bhee-2020-0007
Tarik Dervišević, Sabina Baraković, J. Husić
{"title":"Case Study: Security of System for Remote Management of Windows","authors":"Tarik Dervišević, Sabina Baraković, J. Husić","doi":"10.2478/bhee-2020-0007","DOIUrl":"https://doi.org/10.2478/bhee-2020-0007","url":null,"abstract":"Abstract In the process of designing and forming each system, it is necessary to identify potential vulnerabilities and threats to that system and to include appropriate countermeasures. The process that helps to find the problem in the first phase of design is called threat modeling. Threat modeling is based on the idea that every system has valuable resources that need to be protected. These resources have certain weak points that internal or external threats can use to harm them, while there are as well countermeasures used to mitigate them. Therefore, this paper analyses the security of a Web of Things (WoT)-based system for remote management of windows, which is in the design stage by using a threat modeling approach based on STRIDE and DREAD. The results obtained through Microsoft Threat Modeling Tool (MTMT) justified the use of threat modeling in the design phase given that we have identified in total 118 threats, with Elevation of privilege class of threats being the most prominent ones. The Information disclosure threats are found to be the ones characterized as medium and low risk ones, while the most represented high-risk threats again come from the Elevation of privilege class of threats.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"84 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120835227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of Threats for Web of Things (WoT) System 物联网系统的威胁分析
B&H Electrical Engineering Pub Date : 2020-12-01 DOI: 10.2478/bhee-2020-0009
Jasmina Kulović, Sabina Baraković, J. Husić
{"title":"Analysis of Threats for Web of Things (WoT) System","authors":"Jasmina Kulović, Sabina Baraković, J. Husić","doi":"10.2478/bhee-2020-0009","DOIUrl":"https://doi.org/10.2478/bhee-2020-0009","url":null,"abstract":"Abstract The Web of Things (WoT) emerges from applying Web technologies to the Internet of Things (IoT) to access information and services of physical objects. These systems are likely to characterize the future of digital environment and they put certain security issues in the story. In order to help detect potential threats to WoT-system that is being built and designed, it is advisory to implement a threat modelling process. Threat modelling is an engineering technique that can be used to identify threats, attacks, vulnerabilities and appropriate countermeasures in the context of a particular application and is a process best implemented at the system design stage. In this paper, we will analyse the threats for WoT-based door management system by using Microsoft Threat Modeling Tool (MTMT) in order to identify potential threats for this system in design phase. Obtained results justified the use of threat modelling in the design phase given that we have identified in total 89 threats, with Elevation of privilege and Denial of Service (DoS) being the most prominent ones. Those threats are characterized as high and medium risk ones.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126900014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Overview of Islanding Detection Methods of Distributed Sources in Distribution Grid 配电网分布式电源孤岛检测方法综述
B&H Electrical Engineering Pub Date : 2020-12-01 DOI: 10.2478/bhee-2020-0010
Dragan Mlakić
{"title":"Overview of Islanding Detection Methods of Distributed Sources in Distribution Grid","authors":"Dragan Mlakić","doi":"10.2478/bhee-2020-0010","DOIUrl":"https://doi.org/10.2478/bhee-2020-0010","url":null,"abstract":"Abstract Increasing number of distribution sources has many benefits: system reliability, energy quality in some cases, voltage stability, power security, etc. Adding advantages include potential disadvantages and risks for the network and its users, in this case consumers and other electricity sources. The disadvantages may be, but are not limited to increased levels of short circuit currents, deliberate disconnection from the distribution network, poor energy quality in some cases, and risk of islanding. Islanding protection has become one of the main requirements when a new distribution source needs to be installed in the network, which requires islanding protection as one of the standard distribution source protections. Many researchers have suggested some solutions to the problem of islanding and, based on previous research, four main parts have been formed: communication-based protection, passive, active, and hybrid methods of protection. This paper reviews current applicable methods in industry and the real sector.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116656636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Realisation of 3Smart Project at Ephzhb Business Building Site in Tomislavgrad 在Tomislavgrad的Ephzhb商业建筑工地实现3Smart项目
B&H Electrical Engineering Pub Date : 2020-12-01 DOI: 10.2478/bhee-2020-0015
Mile Međugorac
{"title":"Realisation of 3Smart Project at Ephzhb Business Building Site in Tomislavgrad","authors":"Mile Međugorac","doi":"10.2478/bhee-2020-0015","DOIUrl":"https://doi.org/10.2478/bhee-2020-0015","url":null,"abstract":"Abstract Efficient use of energy is important in achieving sustainable development. In 2007, European Union set now well-known targets (20-20-20) for 2020 regarding greenhouse gas emissions, energy consumption share obtained from renewable energy sources and more efficient use of energy. These goals were groundbreaking at the time. They set a clear sense of direction, which drove investment in infrastructure, and research and innovation. It was a concept that has now been followed by countries all over the world. In 2019, European Union set even more challenging goals for 2030. An important role in achieving energy efficiency goal have building energy management systems, because consumption of commercial and residential buildings has more than 30% of final energy consumption amount. That is why efficient and intelligent energy management in the buildings can have considerable benefits. 3Smart project is an international project, which links renewable energy sources and energy efficiency with biggest achievement in applications, which manage energy flows in a building in interaction with electrical distribution network. The expected impact is clean and efficient way of energy usage with lower costs.","PeriodicalId":236883,"journal":{"name":"B&H Electrical Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116641531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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